Interior of a drum washing machine includes an outer drum and an inner drum. The outer drum is provided with a heating tube, and the outer drum is used to store water for washing clothes. And the inner drum performs a beating-type washing when it rotates. The inner drum contains a number of small holes, the inner drum is used to isolate the clothes from washing water when spinning the clothes.
In related arts, a method of washing the clothes is generally carried out so that the washing water is heated at a main washing stage to promote activation of detergent to improve washing effect. However, the above washing method cannot achieve the purpose of stretching the clothes and removing wrinkles of the clothes, and the washing time is too long. There are also washing machines that use a steam generator to provide steam. The clothes to be washed are fully wetted by the washing water, and then a steam washing is performed, so as to allow the clothes to be stretched and remove wrinkles of the clothes. Meanwhile, time of the main washing by the steam washing is reduced. However, due to the fact that the clothes contain a large amount of moisture after being wetted, it is difficult for the clothes to absorb the steam, thereby reducing the effect of the steam washing. As a result, the washing time is still longer, and energy consumption is excessive.